CVE-2023-52772 – This is a use-after-free vulnerability in the L... (How to Fix)

Q: What is the severity of CVE-2023-52772?

CVE-2023-52772 has a CVSS score of 7.8 (HIGH). This is a use-after-free vulnerability in the Linux kernel's AF_UNIX socket implementation that allows a local attacker to potentially crash the system or execute arbitrary code. It affects Linux systems with vulnerable kernel versions when using UNIX domain sockets. The vulnerability occurs when one thread modifies out-of-band data while another thread is reading it, leading to memory corruption.

📋 TL;DR

This is a use-after-free vulnerability in the Linux kernel's AF_UNIX socket implementation that allows a local attacker to potentially crash the system or execute arbitrary code. It affects Linux systems with vulnerable kernel versions when using UNIX domain sockets. The vulnerability occurs when one thread modifies out-of-band data while another thread is reading it, leading to memory corruption.

💻 Affected Systems

Products:

Linux Kernel

Versions: Specific vulnerable versions not explicitly stated, but based on commit history, likely affects multiple stable kernel versions before the fix.

Operating Systems: Linux distributions using vulnerable kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Requires UNIX domain socket usage. The vulnerability is in the AF_UNIX implementation which is commonly used for inter-process communication.

📦 What is this software?

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Local privilege escalation to kernel-level code execution, potentially leading to full system compromise.

🟠

Likely Case

Kernel panic leading to system crash and denial of service.

🟢

If Mitigated

Limited to denial of service if exploit attempts are detected and blocked.

🌐 Internet-Facing: LOW - This is a local vulnerability requiring access to the system.

🏢 Internal Only: HIGH - Local users or compromised services can exploit this to escalate privileges or crash systems.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires local access and knowledge of the race condition timing. The vulnerability was discovered by syzbot fuzzing.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Kernel versions with commits 069a3ec329ff43e7869a3d94c62cd03203016bce or later

Vendor Advisory: https://git.kernel.org/stable/c/069a3ec329ff43e7869a3d94c62cd03203016bce

Restart Required: Yes

Instructions:

1. Update Linux kernel to patched version. 2. Check distribution-specific security advisories. 3. Reboot system after kernel update.

🔧 Temporary Workarounds

Disable UNIX domain sockets

linux

Prevent usage of AF_UNIX sockets which may break inter-process communication

Not practical as it would break many system functions

🧯 If You Can't Patch

Restrict local user access to minimize attack surface
Implement strict process isolation and privilege separation

🔍 How to Verify

Check if Vulnerable:

Check kernel version and compare with patched versions. Vulnerable if using kernel before fixes in commit 069a3ec329ff43e7869a3d94c62cd03203016bce

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version includes the fix commit or is from a distribution that has backported the patch

📡 Detection & Monitoring

Log Indicators:

Kernel panic logs
KASAN reports of use-after-free in unix_stream_read_actor

Network Indicators:

Not applicable - local vulnerability

SIEM Query:

Search for kernel crash logs containing 'unix_stream_read_actor' or 'KASAN: slab-use-after-free'

📊 Metadata

CVE ID: CVE-2023-52772

CVSS v3 Score: 7.8 (HIGH)

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE: CWE-416

Published: May 21, 2024

Last Updated: November 21, 2024

🔗 References

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2023-52772, you might also want to check these: